I would just stop any contact with her outside of pleasant friendliness at group events. A number of the things you are saying are her trying to be hurtful don't necessarily come across as that way to me, but since they do to you, I would not hang out with her, as clearly she isn't going to change if she doesn't even understand there's a problem.
Stick to respectful, and stop worrying about being a friend. If it's also a problem because the three of you are in the same place together OFTEN, then I might want to see about if he is willing to have some dates where only one of you is present, so you can still enjoy your group of friends without having to deal with with her every time you go out.
Happiness will never come to those who fail to appreciate what they already have.